78140987 has 4 divisors (see below), whose sum is σ = 80661696. Its totient is φ = 75620280.

The previous prime is 78140981. The next prime is 78140999. The reversal of 78140987 is 78904187.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 78140987 - 2⁴ = 78140971 is a prime.

It is a super-2 number, since 2×78140987² = 12212027698668338, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78140981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1260308 + ... + 1260369.

It is an arithmetic number, because the mean of its divisors is an integer number (20165424).

Almost surely, 2^78140987 is an apocalyptic number.

78140987 is a deficient number, since it is larger than the sum of its proper divisors (2520709).

78140987 is a wasteful number, since it uses less digits than its factorization.

78140987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2520708.

The product of its (nonzero) digits is 112896, while the sum is 44.

The square root of 78140987 is about 8839.7390798598. The cubic root of 78140987 is about 427.5231445582.

The spelling of 78140987 in words is "seventy-eight million, one hundred forty thousand, nine hundred eighty-seven".